Difficult that one. I suppose your perception of the noise might not be the same as some other people who might think it OK. So if you didn't declare that your neighbours were noisy how could anybody take you to task - it may be that you didn't think they were particularly noisy. Flats and maisonettes are always going to pose that sort of problem.
Has there been an issue about the noise from other neighbours, have the police been contacted? If any official complaints had been received it might make a difference as to whether you would be best to declare it.
I wrote the above before deciding to look this up and found this very helpful link for you dorothee
http://www.problemnei...oblem-neighbours.html
Good luck.